TY  - JOUR
A1  - Panzer, Sabine
A1  - Brych, Annika
A1  - Batschauer, Alfred
A1  - Terpitz, Ulrich
T1  - Opsin 1 and Opsin 2 of the corn smut fungus ustilago maydis are green light-driven proton pumps
JF  - Frontiers in Microbiology
N2  - In fungi, green light is absorbed by rhodopsins, opsin proteins carrying a retinal molecule as chromophore. The basidiomycete Ustilago maydis, a fungal pathogen that infects corn plants, encodes three putative photoactive opsins, called ops1 (UMAG_02629), ops2 (UMAG_00371), and ops3 (UMAG_04125). UmOps1 and UmOps2 are expressed during the whole life cycle, in axenic cultures as well as in planta, whereas UmOps3 was recently shown to be absent in axenic cultures but highly expressed during plant infection. Here we show that expression of UmOps1 and UmOps2 is induced by blue light under control of white collar 1 (Wco1). UmOps1 is mainly localized in the plasma membrane, both when expressed in HEK cells and U. maydis sporidia. In contrast, UmOps2 was mostly found intracellularly in the membranes of vacuoles. Patch-clamp studies demonstrated that both rhodopsins are green light-driven outward rectifying proton pumps. UmOps1 revealed an extraordinary pH dependency with increased activity in more acidic environment. Also, UmOps1 showed a pronounced, concentration-dependent enhancement of pump current caused by weak organic acids (WOAs), especially by acetic acid and indole-3-acetic acid (IAA). In contrast, UmOps2 showed the typical behavior of light-driven, outwardly directed proton pumps, whereas UmOps3 did not exhibit any electrogenity. With this work, insights were gained into the localization and molecular function of two U. maydis rhodopsins, paving the way for further studies on the biological role of these rhodopsins in the life cycle of U. maydis.
KW  - Ustilago maydis
KW  - patch-clamp
KW  - fungal rhodopsins
KW  - microbial rhodopsins
KW  - acetate
KW  - indole-3-acetic acid
KW  - structured illumination microscopy
KW  - sporidia
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201453
VL  - 10
ER  - 
TY  - JOUR
A1  - Adam, Alexander
A1  - Deimel, Stephan
A1  - Pardo-Medina, Javier
A1  - García-Martínez, Jorge
A1  - Konte, Tilen
A1  - Limón, M. Carmen
A1  - Avalos, Javier
A1  - Terpitz, Ulrich
T1  - Protein activity of the \(Fusarium\) \(fujikuroi\) rhodopsins CarO and OpsA and their relation to fungus−plant interaction
JF  - International Journal of Molecular Sciences
N2  - Fungi possess diverse photosensory proteins that allow them to perceive different light wavelengths and to adapt to changing light conditions in their environment. The biological and physiological roles of the green light-sensing rhodopsins in fungi are not yet resolved. The rice plant pathogen Fusarium fujikuroi exhibits two different rhodopsins, CarO and OpsA. CarO was previously characterized as a light-driven proton pump. We further analyzed the pumping behavior of CarO by patch-clamp experiments. Our data show that CarO pumping activity is strongly augmented in the presence of the plant hormone indole-3-acetic acid and in sodium acetate, in a dose-dependent manner under slightly acidic conditions. By contrast, under these and other tested conditions, the Neurospora rhodopsin (NR)-like rhodopsin OpsA did not exhibit any pump activity. Basic local alignment search tool (BLAST) searches in the genomes of ascomycetes revealed the occurrence of rhodopsin-encoding genes mainly in phyto-associated or phytopathogenic fungi, suggesting a possible correlation of the presence of rhodopsins with fungal ecology. In accordance, rice plants infected with a CarO-deficient F. fujikuroi strain showed more severe bakanae symptoms than the reference strain, indicating a potential role of the CarO rhodopsin in the regulation of plant infection by this fungus.
KW  - fungal rhodopsins
KW  - CarO
KW  - OpsA
KW  - Fusarium fujikuroi
KW  - Oryza sativa
KW  - rice–plant infection
KW  - green light perception
KW  - indole-3-acetic acid (IAA)
KW  - bakanae
KW  - patch-clamp
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-285125
SN  - 1422-0067
VL  - 19
IS  - 1
ER  -